1. Field of the Invention
The present invention relates to a planar antenna and a wireless communication apparatus. More particularly, the present invention relates to a planar antenna without a through-hole structure and a wireless communication apparatus
2. Description of Related Art
With development of hardware device and technique for wireless transmission, a multi input multi output (MIMO) technique has become an important indicator for a high efficiency wireless communication technique, and gradually becomes a main stream for future wireless communication. Different to a conventional design of a single antenna, the MIMO technique applies multi antennas to achieve multi-path transmission of a wireless network. Moreover, the MIMO technique has advantages of improving a transmission speed and a signal-receiving range of the wireless network, etc.
In the wireless network mainly applying the MIMO technique, the wireless communication apparatus has to apply a plurality of antennas to implement the multi-path transmission mechanism. For example, assuming a wireless local area network (WLAN) applies a 3×3 MIMO system, and a worldwide interoperability for microwave access (WiMAX) applies a 2×2 MIMO system, the wireless communication apparatus then has to utilize 5 antennas for being applied to the WLAN and WiMAX.
However, a cost of a single antenna is about 20-30 NT presently, so that 100-150 NT have to be spent for the antenna cost of the wireless communication apparatus. Moreover, as a number of the inbuilt antenna increases, a system manufacture has to spend more human labours and time for assembling the antennas. In other words, when a plurality of antenna is applied to the wireless communication apparatus, the antenna size, the material cost and the labour cost for assembling are greatly increased.